Summary: | 碩士 === 國立雲林科技大學 === 環境與安全衛生工程系 === 107 === Fenton and sunlight photo-Fenton photodegradation of aqueous Rhodamine B (Rh B) were carried out using zero-valent iron Fe(0) as a catalyst to investigate the effect of different dosing amounts of hydrogen peroxide (H2O2) and zero-valent iron on degradation. The experimental results showed that using Fenton completely degraded Rh B with an initial concentration of 20 mg/L at 2.0 mM H2O2 and 17.86 mM of Fe(0), however using the photo-Fenton method only required 0.5 mM of H2O2 and 8.92 mM of Fe(0) to completely decompose Rh B at the same initial contaminant concentration. Moreover, the removal efficiency of organic matter compared that using Fenton was a COD removal rate of only 36.36% for Rh B, and using photo Fenton reached 78.79%. This study highlights the utility of the photo Fenton method in the use of sunlight. Since the Fe(0) is fine-grained and has the feasibility of repeated use, this study used a linear estimation of the removal rate under each batch (reaction time of 20 minutes) then nine repeated experiments, and predicted at least 33 times to be reused at 50% of the residual pollutants as the endpoint. According to the optimized dose cost analysis, if Fenton did not recycle and use Fe(0) at a dose of 17.86 mM and a H2O2 of 2.0 mM, the dosing cost was 213.71 NT dollars/ton of wastewater, while photo Fenton added the dose only required a Fe(0) of 8.92 mM and a H2O2 of 0.5 mM, basing on zero-valent iron reused for at least 33 times, the cost of dosing calculated to be 8.81 NT dollars/ton of wastewater.
To sum up, sunlight photo Fenton effectively and rapidly degraded the refractory pollutant Rh B in water and using Fe(0) as a reused catalyst, at the same complete degradation effect, photo Fenton greatly reduced the cost from dose.
|